From its initial focus on chlamydial molecular pathogenesis and intracellular development, this research program has expanded to include a second objective: the development of a vaccine against blinding trachoma, a-widespread sequela of chlamydial ocular disease in developing countries. The initiation of this project was greatly facilitated by the considerable overlap in reagents and technologies with his prior interest and the development of key collaborations with established immunologists at the University of Rochester and at the University of Arkansas for Medical Sciences. The research objectives are: the functional and structural characterization of a chlamydial adhesin, the study of the role of a chlamydial chaperonin in the synthesis/assembly of the chlamydial cell wall, and the identification of chlamydial protective antigens and their evaluation as vaccine components.